Apparatus for making multiple plastic bags with reclosable fastener thereon

ABSTRACT

A mechanism and method for making material for multiple plastic bags with reclosable fasteners thereon, including either continuously supplying a flattened plastic film tube and cutting a strip from the front wall to expose the rear wall or supplying a flattened film sheet and folding back both ends so as to leave a central exposed section and applying a rear fastener strip to the rear wall or exposed section of the film and applying front fastener strips to the edges of the front wall or folded ends of the film, positioning an anvil within the film and simultaneously applying high speed continuous heat sealing means such as ultrasonic sealing horns to the web portions of the fastener strips and film to form a seal, and thereafter joining the front fastener strips to the rear fastener strip and rolling the material on a supply roll for later cutting the bags down the center of the rear fastener strip, or else continuously supplying a flat film sheet and guiding one or more sets of fastener strips to the surface of said film sheet, positioning an anvil below said film and simultaneously applying high speed continuous heat sealing means, such as an ultrasonic sonic process, to the surface of the web portions of the fastener strips and film sheet to form a continuous seal, and joining and cutting between the fastener strips as required, and cross cutting the assembly to form a series of bags.

United States Patent [191 Ausnit Dec. 10, 1974 APPARATUS FOR MAKINGMULTIPLE PLASTIC BAGS WITH RECLOSABLE FASTENER THEREON [76] Inventor:Steven Ausnit, 124 E. 61st St., New York, NY. 10021 [22] Filed: July 25,1972 [21 Appl. No.: 275,063

[52] US. Cl. 156/580, 24/201, 156/66,

[51] Int. CL... A44b 17/00, B32b 7/08, B290 27/08, 823k 29/00 [58] Fieldof Search 24/201 C; 156/66, 73, 580, 156/583; 150/3; 53/40; 161/48Primary Examiner-Philip Dier Attorney, Agent, or FirmHil1, Gross,Simpson, Van Santen, Steadman, Chiara & Simpson 5 7] ABSTRACT Amechanism and method for making material for multiple plastic bags withreclosable fasteners thereon, including either continuously supplying aflattened plastic film tube and cutting a strip from the front wall toexpose the rear wall or supplying a flattened film sheet and foldingback both ends so as to leave a central exposed section and applying arear fastener strip to the rear wall or exposed section of the film andapplying front fastener strips to the edges of the front wall or foldedends of the film, positioning an anvil within the film andsimultaneously applying high speed continuous heat sealing means such asultrasonic sealing horns to the web portions of the fastener strips andfilm to form a seal, and thereafter joining the front fastener strips tothe rear fastener strip and rolling the material on a supply roll forlater cutting the bags down the center of the rear fastener strip, orelse continuously supplying a flat film sheet and guiding one or moresets of fastener strips to the surface of said film sheet, positioningan anvil below said film and simultaneously applying high speedcontinuous heat sealing means, such as an ultrasonic sonic process, tothe surface of the web portions of the fastener strips and film sheet toform a continuous seal, and joining and cutting between the fastenerstrips as required, and cross cutting the assembly to form a series ofbags.

14 Claims, 17 Drawing Figures PNEMH, ZEE l (MEN APPARATUS FOR MAKINGMULTIPLE PLASTIC BAGS WITH RECLOSABLE FASTENER THEREON BACKGROUND OF THEINVENTION The present invention relates to improvements in methods andmechanism of forming material which is used for making multiple bags.More particularly, the invention relates to a method and mechanism forarranging and handling the film and the strip for the fasteners for thebags and for joining the fastener strips to the film by high speedcontinuous heat sealing means such asby an ultrasonic sealing process inan improved manner which forms an improved bag and which is capable ofcontinuous fast production operation, that can be used in conjunctionwith extrusion operations.

In the formation of plastic film bags of the type referred to, the bagsare of plastic film and usually formed with a folded bottom edge andwith side edges sealed to each other. Flexible reclosable plasticfastener strips are sealed to the top edges of the bags therebyproviding a reclosable scalable bag unit.

The fastener strips may take various forms such as shown in U.S. Pat.No. 2,780,261, Svec et al.

In the manufacture of bags such as illustrated in the above Svec et alPatent, the bag bodies are formed of a thin lightweight plastic filmwhich is extruded separately from the fastener. The fastener strips areextruded of a material and with a process that provides interlocking ribandgroove elements carefully shaped and sized so that they willinterlock when pressed together and will separate when pulled apart byopening flanges. These strips have web portions which are sealed to thefilm of the bag. It has been discovered that the bags in question can bemanufactured by a multiple operation, that is, the material for makingthe bags can be formed so that two bag bodies project from a centerassembly of the fastener strips. By cross cutting and seaming across thelength of the material made, two

bags are formed simultaneously. Since the overall cost of the completedbags is a function of the speed at which they can be manufactured, it isimportant that the length of material from which the bags are to be madecan be made smoothly and rapidly at production rates of speeds, and in areliable fashion. Improper joining of the fastener strips to the film ofthe bag will result in leaks in the bag, and in bags that will notproperly close or cannot be reopened due to distortion of the fastenersbecause of misalignment. Also the amount of heat for joining thefastener to the bag wall will have an effect on the seal. Ifinsufficient heat is applied, the seal will be inadequately formed sothat the bag will leak, or the fastener web will peel away from the filmto which it is attached. If too much heat is applied, the plastic willmelt away so that there may be holes in the wall of the bag as mentionedabove. It is also important for the fastener strips and the bag film tobe accurately oriented with respect to each other. If the film is notproperly positioned relative to the web portion of the fastener strips,a good seal may not result, and projecting raw edges of plastic on theinside of the bag can form crevices in which the contents of the bagwill be caught, or if on the outside of the bag, said edges will tend tobe torn apart by the user of the bag who will mistake these edges forthe fastener opening lips. In the described form of manufacture, thefastener and the film are made separately by an extrusion process andthen joined together shortly thereafter in an in-line process featuringcontinuous heat sealing of the strip to the film. Heretofore, fastenerbags were made in an operation which required, in addition to the crossseal, attaching the fastener to the film during the bag making operationby intermittent overlapping sealing of the fastener web to the film,which in turn, out down on the speed of the operation and reliability ofthe fastener seal. This was because each seal cycle first required abuild up of heat and then a cooling of the seal formed before theoperation could be repeated. This prevented the fastner and the filmfrom being attached together continuously as they were being extruded.

Additionally, the heat could never be closely controlled since it was,as indicated, continuously varying through its cycle. Under the presentinvention, once the optimumextrusion speeds have been reached, theheating means required for joining the fastener to the film can be setand maintained within a fairly accurate degree. The system describedalso has an advantage over methods of making a film and fastenerintegrally in that it allows the use of the most desirable resins forthe film, where clarity and strength are required, and for the fastenerwhere sufficient slip and contour forming are required. Generally, thecharacteristics of the resins required for the fastener are not the sameas those required for the film and integral fastener film constructionsusually result in a compromise. Furthermore, by extruding the fastenerand. the film separately, the most desirable extrusion process andcooling and control can be used for each one, thereby increasing thespeeds at which each can be manufactured over that at which they can bemanufactured integrally.

Accordingly, one of the best ways of making reclosable fastener bags isto be able to join the fastener and the film together as they are beingseparately extruded, on a continuous reliable basis, and laterconverting the fastener film into the bags themselves. After joining ofthe strip to the film, the material is placed on a roll for shipment toa converter, who in turn, forms bags by cross cutting and sealing. It isessential to the original manufacturer of the material that it beproperly made so that the material can be rolled and stored.

It is accordingly an object of the present invention to provide animproved mechanism for forming continuous material for making fastenerbags which is capable of operating at extrusion production speeds andproducing bag material which is accurately and reliably made.

Another object of the present invention is to provide a mechanism forcontinuously forming material for making multiple bags, which canoperate at extrusion production speeds eliminating the possibility offorming melted holes in the plastic and insuring positive and optimumattachment between the bag film and fastener strips.

Still another object of the invention is to provide a mechanism whichwill untilize tubular film or folded sheet film or flat sheet film andwill attach front and rear fastener strips for bags by simultaneouscontinuous production operation.

Other objects, advantages and features, and equivalent structures withinthe scope of the invention will become more apparent to those skilled inthe art in connection with the teaching of the principles thereof in thespecification, claims, and drawings in which:

DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view with portionsbroken away of a bag of the type made from material for makingreclosable fastener bags;

FIG. 2 is a somewhat schematic top plan view of a mechanism for makingbag material embodying the principles of the present invention;

FIG. 3 is a vertical sectional view taken substantially along lineIII-III of FIG. 2;

FIGS. 4 through are vertical sectional views taken through the mechanismof FIG. .2 at different stages along the machine at the locationsindicated by the corresponding Roman numeralled sections lines in FIG.2;

FIG. 1 1 is a perspective view of a portion of the structure of FIG. 2;

FIG 12 is another perspective view illustrating another form of theinvention;

FIG. 13 is a vertical sectional view taken at the location of XIII-XIIIof FIG. 2 and illustrating another form of the invention;

FIG. 14 is a fragmentary perspective view illustrating a modified formof anvil which may be employed;

FIGS. 15 and 16 are cross-sectional views illustrating a form of theinvention which uses a flat sheet film and fastener of slightlydifferent construction; and

FIG. 17 is a cross-sectional view illustrating a step in the completionof the bag formed as illustrated in FIGS. 15 and 16.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates a bag of thetype which is formed from material made on the mechanism and with themethod of the present invention. The bag is the ultimate end product,and the continuous material for making bags is often first manufacturedand then rolled on a roll to be made into bags by a final operation at abag making shop. The bag has a lower bag body portion 10 of thin pliableplastic film such as polyethylene or other suitable plastic. Attached atthe upper edges of the bag are fastener strips 11 and 12. The frontfastener strip 1 1 is attached to the upper front wall 10a of the bag bya heat seal at 13, and the rear fastener strip 12 is attached to theupper edge of the rear wall 10b at 14 by a heat seal. References will bemade herein to front and rear for identifying the location of walls ofthe bag and also to upper and lower for identification of parts of thefastener strips, but it will be understood that in the operation of themachine, the bag material may be handled in different positions, and thereference to locations is to be considered as relative to the otherpositions of the machine, and these terms are not intended to belimiting in the specification or claims. Also, the fastener strip 11 mayhave a different configuration as in FIG. 15.

The front or upper fastener strip 1 1 has a web portion 15 by which itis attached to the front wall 100 of the bag. The rear or lower fastenerstrip 12 has a web portion 16 by which it is attached to the upper edgeof the rear wall 10b of the bag. The front fastener strip also has athickened marginal portion 18 which carries ribs and grooves tointerlock with mating ribs and grooves in the thickened marginal portion17 of the rear fastener strip.

In accordance with the method employed in making bags with the preferredstructure of the present invention, a continuous length of material isproduced which contains bags on each side so that it is cut down thecenter to separate the bags. To form the bags themselves, an end iscross-cut from the length of material, and as the edges are severed, aseam is also formed for the bag. The appearance of the length ofmaterial with the fastener joined, from which dual bags aresimultaneously formed by crosscutting and sealing, is shown in FIG. 10.This construction is also shown in US. Pat. No. 3,219,084, Ausnit et al.

As shown in FIG. 2, a continuous length of plastic tubing 21 is fed intothe machicne, such as from a supply roll or from an extruder. The tubingis a thin, lightweight plastic which will form the bodies of the bags.FIG. 2 is looking down upon the mechanism, and the various anvils andparts are supported by suitable frame mechanism which is omitted for thesake of clarity.

The tubing first passes a slitting station at which are located spacedknives 24 and 25, as in FIG. 5. These knives cut a strip 16 from thecenter of the upper wall 22 of the tube so as to leave a slot as in FIG.6. The strip 26 which is removed leaves out edges 27 and 28 which formthe upper edges of the front walls of the opposed bags. To these edgeswill be attached the front or upper fastener strips. The strip 26 whichus out from the tubing is discarded. In some arrangements it may bedesired to cut a single slit in the tubing and to separate the edgesformed thereby to form the open slot as illustrated in FIGS. 2 and 6. Inother arrangements, a flat sheet may be taken and folded at either endto yield a configuration as illustrated in FIG. 6. In yet anotherarrangement, the fastener strips can be applied to the surface of a flatsheet as in FIG. 15.

The slitting knives 24 and 25 are carried on a suitable mandrel such asshown at 29 and will function to continuously cut the tube 21 which ismoved over the mechanism, such as by being pulled forwardly at acontinuous rate of speed by take-up roll, not shown, upon which thecompleted material is wound, which roll is located at the take-upstation E. As the tubing passes through the machine, it first passes theslitting station A, next a lay-on station B where the upper fastenerstrips are laid over the edges of the tubing, then a separating stationI3 where the upper fastener sections are separated from the lowerfastener section, and next passes a sealing station C where the edges ofthe fastener strips are continuously attached to the edges of the film,thereafter it passes a joining station D where the fastener strips areinterlocked, and thence it passes to the take-up station E where thecompleted material is wound up.

At the lay-on station E is a guide or positioning roll 34 positionedabove the tubing and having annular channels 34a and 34b which guide theupper fastener profile strips 31 and 32 into place over the edges 27 and28 of the material. The profile fastener strips are positioned so thattheir web edges 31a and 320, FIG. 7, overlay the edges 27 and 28 of theplastic film. Accurate orientation is necessary in the present instanceinasmuch as the web portions are sealed to the film by continuous heatsealing means such as with ultrasonic heads which are capable of forminga sealing operation without inadvertently placing holes through theplastic. The seam formed between the marginal portions of the fastenerstrips and the film can be carried completely to the edges of both thefilm and web portion so that the full area of overlap can be employedfor the seal. This avoids projecting unbonded edges above or below theseam as can occur if the seal does not cover the entire area of overlap.

Beneath the film is a supporting roller 35, and the rollers 34 androtate at the speed of travel of the moving film.

Also fed over the positioning roll 34 is a lower fastener strip which isattached to the lower portion 21b of the film. The back fastener strip36 passes down through the opening between the edges 27 and 28 in thefilm and is laid down against the lower portion 21b of the film as shownin FIGS. 7 and 8. This back fastener strip 36 has profiles 36a and 36bat the edge, and a web portion 36c in the center. This web portion 36cwill be welded to the lower wall 21b of the film with a broad seal, andwhen the bags are formed, a cut will be made in the center of the sealso that one-half of the strip 36 will go with each bag.

The film is then passed over and under a main anvil which has upper andlower support surfaces for the film. The web portions of the upperclosure strips 31 and 32 and the edges of the upper film walls 27 and 28pass between the continuous heat sealing means 41 and 42 and the anvilupper support surface to be sealed together. Beneath the anvil 40 isanother continuous heat sealing means 43 which seals the fastener centerweb portion 360 to the center of the lower film wall 21b. The seamsformed are shown beneath the marginal portions 31a and 32a, and beneaththe marginal portion 360 as in FIG. 9.

Various sealing mechanisms may be used. One form which can be used is anultrasonic sealer and the structure will be described as employing thistype of sealer. Each of the continuous heat sealing means 41, 42 and 43,if it uses ultrasonic means, has a head or horn operated by a sonicconverter which receives power from a power supply. The head may be inthe form of a horn which can move downwardly to engage the overlappedportions of the plastic. The application of utrasonic force through thehorn is supplied for a sufficient fraction of length of time to inducefusion between the surfaces of the layered material, and they are heldin that relative position for a sufficient fraction of time until theplastic has solidified adequately to maintain the portions in theirrelative positions. The power supply converts conventional cycle persecond electrical energy to 20,000 cycle per second energy. The 20,000cycle per second is chosen as optimum, but higher frequencies may beemployed. A control is provided to regulate the frequency and energyapplication to the film and to the web portion of the fastener strip. Asthe speed of the film is increased or decreased, the frequency may beincreased or decreased and maintained at an optimum range so as to allowuniform and complete formation of the ultrasonic seal between layers.The power supply feeds the 20,000 per second electrical energy to thesonic converter which converts the electrical energy to mechanicalvibrations at the same frequency in the horn. The horn is placed intocontact onto the plastic layers, holding them against the anvil, and thevibrations travel through the plastic to the boundary between thesurfaces of the layers where they are joined. At the location of thesurfaces between the layers, the intense vibrations of one surfacemoving against the other causes sufficient frictional heat to createfusion of the plastic with the material staying under the horn and incontact therewith the fraction of time long enough for the fusion totake place.

With the arrangement, the plastic layers can be of differentthicknesses, as they probably will be with changes in. thickness of filmand retention of the same thickness of web portion of fasten-er strip.Also, since the heat is generated between the surfaces of the layersthemselves, they can be welded up to their extreme edges. Since theenergy transmitted to the plastic can be controlled by accuratelycontrolling the frequency of the ultrasonic vibrations, immediatecontrol can be obtained relative to the speed of travel of the filmwhich is an overall controlling factor.

The film after leaving the separating anvil next passes to station Dwhere the front fastener strips 31 and 32 are pressed into interlockingengagement with the rear fastener strip 36 as in FIG. 10. For thispurpose a joining and guide roll presses down upon the strips tointerlock their rib and groove elements. The roll 50 has annularchannels 51 and 52 which align the fastener strips 31 and 32 and pressthem into interlocking engagement.

FIG. 1 1 shows the anvil 40 in greater detail. The anvil has a roundedleading nose end 40a which is smoothed to insure separation of the lowerfastener strip from the upper fastener strips 31 and 32. The anvil has asmooth upper surface 40b to support the film, and the fastenerstrips 31and 32 thereon, so that the continuous heat sealing means 41 and 42 canengage the web portions 31a and 32a and the film edges 27 and 28 to formthe continuous heat seal. Similarly, the lower suface 400 of the anvilis smooth so that the sealing means 43 can form its seal, sealing thelower film to the web portion 360 of the lower fastener strip 36.

Should ultrasonic means be used for sealing inasmuch as such seals areformed by the transmission of vibrational energy, anvil 40' shown inFIG. 14 is separated so that it has an upper part 40f and a lower part40g. These parts are separated by sound deadening material 40h.

FIG. 12 illustrates another form of anvil. In this anvil 60, acontinuous heat sealing means 64 fastens the lower fastener strip 36 tothe lower film 21b by extending downwardly from the top and engaging thefilm and strip between itself and a lower anvil 61a. To accommodatethis, the anvil 60 is provided with a recess in its trailing edge sothat projecting portions 60a and 60b have a recess 600 between them intowhich the continuous heat sealing means 64 extends. The lower anvil 6111also supports the film, and a shoe 61 is positioned beyond the anvil 60and below the fastener strip joining roll 62 which presses the fastenerstrips together, between shoe 61 and the joining roll 62. The loweranvil 61a and plate 61 can be made in one piece.

In the structure shown in FIG. 13, an anvil is provided which has guidesfor additionally guiding the fastener strips. in the lower surface ofthe anvil 70 are grooves 70a and 70b for the fastener portions of thefastener strip 36. Plates and 76 beneath the anvil help support the film21.

At the upper side of the anvil are L-shaped guide strips 71 and 72.These are held on the anvil by thumb screws 73 and 74, and providechannels for the fastener portions of the strips 31 and 32. Thesechannels hold the strips accurately in place maintaining accurateorientation for the continuous heat sealing mens 41 and 42.

FIG. illustrates an arrangement wherein a sheet instead of a tube isused. It will, of course, be understood that the principles of theFigures decribed earlier herein may also be used with a fiat sheet sothat sides of the sheet are folded inwardly with the edges being at 27and 28 in FIG. 2, instead of cutting a strip from a tube. Also, insteadof cutting a strip from a single slit may be formed with the sides ofthe slit spread.

In FIG. 15, the fiat sheet is shown as a laminated unit having plurallayers with an inner layer 80a and an outer layer 80b. The outer layermay be a rough protective sheet, and the inner layer 80a may be ofplastic so as to provide air-tightness to the bag unit. A strip 90having shaped releasably interlocking fastener profiles 84 and 85thereon is attached to the laminate sheet 80. The sheet is fedcontinuously through a mechanism as illustrated in the previousdrawings, but with an anvil 83 beneath the sheet and sealing horns 86,87 and 88 above the sheet. These horns may be ultrasonic sealers orsealing mechanisms of other contructions, and form a continuous heatseal between the strip 90 and the sheet 80. The seals are formed at 89,90 and 91 as the sheet and strip are fed through the machine in acontinuous process.

In the arrangement of FIG. 16, a multiple layered laminate sheet 93 isprovided, but the interlocking profiles are carried on separate strips.That is, strips 94 and 95 are laminated to the sheet. The strips have amale profile 96 and a female profile 97 respectively thereon.

As the sheet 93 with the strips positioned thereon is fed through themachine in a continuous operation, sealing horns 99, 100, 102 and 103seal the strips to the sheet 93. Seals are formed at 94a and 94b for thestrip 94, and at 95a and 95b for the strip 95. The sealing horns may beultrasonic sealers, or may be other forms of sealing units, and apply asealing pressure with the sheet being supported on the anvil 98 belowthe sheet. The sheet is then folded at 106 with one side brought over asshown by the arrowed line 109, and individual bags are formed bycross-sealing and cutting the folded sheet.

The bottom edges remain separated after crosssealing and cutting, andthe bag is then filled with the product it is to contain. Thereafter tocomplete the bag, the ends of the sheet 93a and 93b are brought intoregistry in the manner shown in FIG. 17, and are heat sealed together bya sealing means 108 against a plate 110.

It is to be noted that an improved bag construction results from themethod and sealing structure shown in FIGS. 15 and 16. In this bagconstruction the profile elements are carried on separate strips, andthe strips are attached to the bag over an area which does not extendbeneath the profile. That is, the areas 96a and 97a of FIGS. 16 and 17directly beneath the profile, are not attached to the material of thebag. This will permit an additional bending flexibility in the stem ofthe male profile 96 and in the base of the female profile 97 which helpsprevent them from being disconnected due to normal twists and stressesand strains on the bag. The flexible profile strips 94 and 95 act asadditional hinges over the small area directly at the base of theprofiles where they are unattached. Yet, the profile strips are firmlyand fully attached to the bag so that no leakage can occur.

I claim as my invention:

1. A mechanism for making multiple plastic bags with reclosablefasteners thereon comprising:

means for continuously supplying flat tubular plastic film; means forforming a continuous opening in the upper layer of the film with theedges of the opening forming the upper edges of front walls of bags tobe made from the film, the portion beneath the upper bag edges formingthe rear wall of the bags;

means for feeding a rear continuous fastener strip having a web portionbetween the edges through the opening and against the rear wall of thefilm;

means for accurately positioning web portions of first and second frontfastener strips against said upper bag edges of the film portion;

first and second continuous high speed heat sealing means attaching saidweb portions of said first and second strips to the film;

and third continuous high speed heat sealing means attaching the webportion of the rear strip to the rear wall of the film.

2. A mechanism for making material for multiple plastic bags withreclosable fasteners constructed in accordance with claim 1 wherein saidcontinuous heat sealing means is in the form of ultrasonic plasticsealers.

3. A mechanism for making material for multiple plastic bags withreclosable fasteners comprising means for supplying plastic film havinga continuous portion for forming the rear wall of bags and having edgeportions extending toward each other over said continuous portion forforming the upper edges of front walls of bags;

means for positioning a rear continuous fastener strip having a centerweb portion between said edge portions and against the rear wall;

means for positioning web portions of first and second front continuousfastener strips respectively against said first and second edgeportions;

at least two continuous heat sealing heads positioned for continuousjoining of the web portions of the front fastener strips to said upperbag edges and a third heat sealing head for joining the web portion ofthe rear fastener strip to the rear wall portion of the film; and meansfor moving said film continuously past said heads.

4. A mechanism for making material for multiple plastic bags withreclosable fasteners in accordance with claim 3 wherein said front andrear heat sealing heads are in opposing relationship and an anvil ispositioned therebetween.

5. A mechanism for making material for multiple plastic bags withreclosable fasteners constructed in accordance with claim 3 andincluding an anvil positioned so that the film passes thereover, andsaid sealing heads including ultrasonic sealing horns opposite the webportion of the fastener strips sealing the web portion to the filmagainst said anvil.

6. A mechanism for making material for multiple plastic bags withreclosable fasteners constructed in accordance with claim 3 andincluding a main anvil positioned to be located beneath said edges ofthe front wall of the film, an opening in the anvil intermediate theside edges thereof, a lower anvil beneath the back wall portion of thefilm opposite said opening, said sealing heads including an ultrasonicsealing means including a pair of horns for sealing the web portions ofthe front fastener strips to the edges of the front film wall againstthe main anvil and including a horn engagable with the web portion ofthe rear film through said opening and sealing said web portion of therear fastener strips to the rear wall of the film against said loweranvil.

7. A mechanism for making material for multiple plastic bags withreclosable fasteners thereon constructed in accordance with claim 6 andincluding a pair of rolls positioned downstream from said anvil pressingthe front fastener strips against the rear fastener strips tointerlocking engagement.

8. A mechanism for making material for multiple plastic bags withreclosable fasteners constructed in accordance with claim 6 andincluding a roller positioned to coact with said lower anvil forpressing the front wall fastener strips against the rear wall fastenerstrip to interengage said strips.

9. A mechanism for making material for multiple plastic bags withreclosable fasteners constructed in accordance with claim 6 andincluding slot means in said main anvil for guiding said strips to aposition relative to said film.

10. A mechanism for making material for multiple bags with reclosablefasteners constructed in accordance with claim 8 and includingadjustable fastener retaining guides receiving and guiding the strips.

11. A mechanism for making material for multiple plastic bags withreclosable fasteners constructed in ac cordance with claim 3 andincluding anvil means positioned opposite each of the sealing heads forcontinuous joining of the front fastener strips and the rear fastenerstrip.

12. A mechanism for making material for multiple plastic bags withreclosable fasteners constructed in accordance with claim 4 andincluding an anvil support positioned to extend between said edgeportions.

13. A mechanism for making material for multiple plastic bagsconstructed in accordance with claim 3 and including slitting means inadvance of the sealing heads for separating said edge portions.

14. A mechanism for making material for multiple plastic bags withreclosable fasteners thereon constructed in accordance with claim 11wherein said anvil 'means has separate upper and lower sections withsound deadening insulating material between said sections.

1. A MECHANISM FOR MAKING MULTIPLE PLASTIC BAGS WITH RECLOSABLEFASTENERS THEREON COMPRISING: MEANS FOR CONTINUOUSLY SUPPLYING FLATTUBULAR PLASTIC FILM; MEANS FOR FORMING A CONTINUOUS OPENING IN THEUPPER LAYER OF THE FILM WITH THE EDGES OF THE OPENING FORMING THE UPPEREDGES OF FRONT WALLS OF BAGS TO BE MADE FROM THE FILM, THE PORTIONBENEATH THE UPPER BAG EDGES FORMING THE REAR WALL OF THE BAGS; MEANS FORFEEDING A REAR CONTINUOUS FASTENER STRIP HAVING A WEB PORTION BETWEENTHE EDGES THROUGH THE OPENING AND AGAINST THE REAR WALL OF THE FILM;MEANS FOR ACCURATELY POSITIONING WEB PORTIONS OF FIRST AND SECOND FRONTFASTENER STRIPS AGAINST SAID UPPER BAG EDGES OF THE FILM PORTION; FIRSTAND SECOND CONTINUOUS HIGH SPEED HEAT SEALING MEANS ATTACHING SAID WEBPORTIONS OF SAID FIRST AND SECOND STRIPS TO THE FILM; AND THIRDCONTINUOUS HIGH SPEED HEAT SEALING MEANS ATTACHING THE WEB PORTION OFTHE REAR STRIP TO THE REAR WALL OF THE FILM.
 2. A mechanism for makingmaterial for multiple plastic bags with reclosable fasteners constructedin accordance with claim 1 wherein said continuous heat sealing means isin the form of ultrasonic plastic sealers.
 3. A mechanism for makingmaterial for multiple plastic bags with reclosable fasteners comprisingmeans for supplying plastic film having a continuous portion for formingthe rear wall of bags and having edge portions extending towArd eachother over said continuous portion for forming the upper edges of frontwalls of bags; means for positioning a rear continuous fastener striphaving a center web portion between said edge portions and against therear wall; means for positioning web portions of first and second frontcontinuous fastener strips respectively against said first and secondedge portions; at least two continuous heat sealing heads positioned forcontinuous joining of the web portions of the front fastener strips tosaid upper bag edges and a third heat sealing head for joining the webportion of the rear fastener strip to the rear wall portion of the film;and means for moving said film continuously past said heads.
 4. Amechanism for making material for multiple plastic bags with reclosablefasteners in accordance with claim 3 wherein said front and rear heatsealing heads are in opposing relationship and an anvil is positionedtherebetween.
 5. A mechanism for making material for multiple plasticbags with reclosable fasteners constructed in accordance with claim 3and including an anvil positioned so that the film passes thereover, andsaid sealing heads including ultrasonic sealing horns opposite the webportion of the fastener strips sealing the web portion to the filmagainst said anvil.
 6. A mechanism for making material for multipleplastic bags with reclosable fasteners constructed in accordance withclaim 3 and including a main anvil positioned to be located beneath saidedges of the front wall of the film, an opening in the anvilintermediate the side edges thereof, a lower anvil beneath the back wallportion of the film opposite said opening, said sealing heads includingan ultrasonic sealing means including a pair of horns for sealing theweb portions of the front fastener strips to the edges of the front filmwall against the main anvil and including a horn engagable with the webportion of the rear film through said opening and sealing said webportion of the rear fastener strips to the rear wall of the film againstsaid lower anvil.
 7. A mechanism for making material for multipleplastic bags with reclosable fasteners thereon constructed in accordancewith claim 6 and including a pair of rolls positioned downstream fromsaid anvil pressing the front fastener strips against the rear fastenerstrips to interlocking engagement.
 8. A mechanism for making materialfor multiple plastic bags with reclosable fasteners constructed inaccordance with claim 6 and including a roller positioned to coact withsaid lower anvil for pressing the front wall fastener strips against therear wall fastener strip to interengage said strips.
 9. A mechanism formaking material for multiple plastic bags with reclosable fastenersconstructed in accordance with claim 6 and including slot means in saidmain anvil for guiding said strips to a position relative to said film.10. A mechanism for making material for multiple bags with reclosablefasteners constructed in accordance with claim 8 and includingadjustable fastener retaining guides receiving and guiding the strips.11. A mechanism for making material for multiple plastic bags withreclosable fasteners constructed in accordance with claim 3 andincluding anvil means positioned opposite each of the sealing heads forcontinuous joining of the front fastener strips and the rear fastenerstrip.
 12. A mechanism for making material for multiple plastic bagswith reclosable fasteners constructed in accordance with claim 4 andincluding an anvil support positioned to extend between said edgeportions.
 13. A mechanism for making material for multiple plastic bagsconstructed in accordance with claim 3 and including slitting means inadvance of the sealing heads for separating said edge portions.
 14. Amechanism for making material for multiple plastic bags with reclosablefasteners thereon constructed in accordance with claim 11 wherein saidanvil means haS separate upper and lower sections with sound deadeninginsulating material between said sections.